A Philadelphia abortion provider won't testify or call witnesses at his capital murder trial, leaving jurors to weigh five weeks of prosecution evidence.

Dr. Kermit Gosnell, 72, is charged with killing four babies allegedly born alive at a clinic that authorities have described as filthy. He is also charged in the 2009 overdose death of a 41-year-old refugee who died months after coming to the U.S.

The jury is expected to hear closing arguments on Monday.

Former employees have testified that Gosnell relied on untrained, unlicensed staff to sedate and monitor women as they waited for abortions. Three workers have pleaded guilty to third-degree murder charges, admitting they helped medicate the adult victim or "snipped" babies' necks after they were born alive to make sure they died.

They told jurors that Gosnell had taught them the technique, and said they trusted that it was legal. At least one, though, admits she grew so concerned about conditions at the clinic that she took pictures of the outdated equipment, messy rooms and stacked specimen jars containing the severed feet of aborted babies.

Gosnell told staff he sometimes kept the samples for DNA purposes in case the pregnancy led to assault charges. Prosecution experts said there were less invasive ways to preserve DNA.

"Once fetuses leave the mother, they are then due the respect that would be given any human being," Assistant District Attorney Ed Cameron argued Tuesday, in support of abuse of corpse charges filed over the severed feet.

Common Pleas Judge Jeffrey Minehart, though, agreed with a defense motion to drop those charges.

Minehart on Tuesday also threw out three of the original seven murder charges involving babies, apparently concluding that the prosecution had not presented enough evidence for the jury to find they were viable, born alive and then killed.

"There is not one piece — not one — of objective, scientific evidence that anyone was born alive," defense lawyer Jack McMahon argued Tuesday, in what is likely a preview of his closing arguments.

McMahon did most of his work by grilling prosecution witnesses, including former clinic workers. Although several said they had seen babies born alive, McMahon suggested the brief movements or breaths they saw were actually involuntary spasms during the death process. He argued that each of the babies had purportedly moved, breathed or whined just once.

"These are not the movements of a live child," McMahon said Tuesday.

One employee, though, has pleaded guilty to killing a baby that was alive for about 20 minutes.

Page 2 of 2 - Expert witness testimony has been another key portion of the case. Prosecutors called neonatologists who estimated that some of the babies were nearly 30 weeks gestation, far past the state's 24-week limit for abortions.

McMahon argued that such dating is imprecise, and that the margin of error is at least two weeks on either side.

The only employee to go on trial with Gosnell, medical school graduate Eileen O'Neill, is charged with theft for allegedly practicing medicine without a license.

She called a string of witnesses this week, most of whom testified about her character. O'Neill, 56, of Phoenixville, then rested Wednesday without taking the stand.